3. Current implementation for ATI adapters

The driver currently supports the SuperVGA capabilities of all ATI adapters
except some early Mach8 and Mach32 adapters that do not provide the required
functionality.
This support works for monochrome, 16-colour and 256-colour video modes, if one
of the following ATI graphics controller chips is present:

The driver also supports 32K, 64K and 16M-colour modes on the 264xT and 3D Rage
series of adapters using the accelerator CRTC (but not the VGA CRTC).

The newer Rage 128 and Radeon chips are not yet supported by this driver.
Rage 128's and Radeon's are, however, supported by separate drivers, and
owners of such adapters should consult the documentation provided with these
drivers.
This driver will also invoke the appropriate driver if it finds Rage 128 and/or
Radeon adapter(s) in the system.

Adapters based on the above chips have been marketed under a rather large
number of names over the years.
Among them are:

Also, a number of mainboards, laptops and notebooks harbour a Mach32 or Mach64
controller.

VGAWonder, Mach8 and Mach32 ISA adapters are available with or without a
mouse.

These adapters are available with a variety of clock generators and RAMDACs.
The 264xT and 3D Rage series of chips are integrated controllers, meaning that
they include a programmable clock generator and a RAMDAC.

For all but Mach64 adapters, this driver still does not provide support for
accelerated drawing to the screen.
This means that all drawing is done by the CPU, rather than by any accelerator
present in the system.
This can make opaque moves, for example, quite ``jerky''.
Also, given that IBM 8514/A and ATI Mach8 do not allow CPU access to their
frame buffer, the driver will currently ignore these accelerators.
Most Mach32 adapters provide both accelerated function and SuperVGA
functionality, but the driver currently only uses the VGA.

The driver does however support the accelerator CRTC present in all
ATI Mach64 adapters.
For 256-colour, and higher depth modes, this support will be used by default,
although an XF86Config option can be specified to use the SuperVGA CRTC
instead.
A linear video memory aperture is also available in 256-colour and higher depth
modes and enabled by default if a 264xT or 3D Rage controller is detected or,
on 88800 controllers, if the accelerator CRTC is used.
XF86Config options are available to disable this aperture, or (for non-PCI
adapters) enable it or move it to some other address.

By default, the driver provides some acceleration for Mach64 if the accelerator
CRTC is used, and modes whose colour depth greater than or equal to 8 are to be
used.
This support is as yet incomplete and can be disabled entirely with an
XF86Config option.

On non-Intel platforms, the driver can, currently, only support PCI Mach64
adapters.